Mill-spout gate



F. B. M- MERCER AND'C. BRADBURN. MILL spourms. APPLICATION mm saw. 12. 1919.

1,427,834; PatentedSept. 5, 1922.

I 2 SHEETS-SHEET l- F. B. M. MERCER AND C. F. BRADBURN.

MILL SPOUT GATE.

APPLICATION man SEPTIIZ, 1919.

1,427,834." nt dsep't. 5, 1922.-

2 SHEETS-SHEET 2.

y fzzven zars, wlffliizmd er a; M15? Patented Sept. 5 1922.

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F E Q a FREDERICK BERNARD MALCOLM IJIEECER, OF TORONTO, AND CHARLES FRANKIE? BRADBURN, 015 TILLSONBURG, ONTARIO, CANADA.

MILL-SPOUT GATE.

Application filed septemb er 12, 191.9. Serial No. 323,420.

To all whom it may concern:

Be it known that we, FREDERICK BERNARD MALCOLM MERGER and CHARLES FRANKLIN BRADBURN, both subjects of the King of Great Britain, and residents of the city of Toronto and the town of Tillsonburg,respectively, both in the Province of Ontario and the Dominion of Canada, have invented certain new and useful Improvements in Mill-Spout Gates, of which the following is a specification.

The herein described invention relates to a means 0]": controlling mill spout gates where the millingmachinery is-driven by electric power and where the failure of the power results in the clogging of the milling machinery.

This invention comprises an electro-magnet having a movable armature provided with a'detent to engage and hold the gate at any position to which it may be opened and to disengage and release the gate on failure of the power, to be automatically closed through the action of a spring or weight.

The electric apparatus and the connections may be applied to existing gates with slight alterations, but it is thought preferable to attach the same to a special housing contain ing a gate and gateway, this housing with its electrical and mechanical apparatus constituting a unit and constructed in such a manner and in such dimensions as to admit of easy application to any standard mill spout through the removal of a section of the same and the fitting of the housing unit within this space.

Figure 1 is a S1Cl6l6V2ll2l0l1 oi; the gate housing and attached apparatus.

Figure 2 is a longitudinal section of theelectro-magnet with detail.

Figure 3 is an elevation of the armature shield or sleeve.

Figure t is an elevation of the armature, extension and detent,

Figure 5 is a cross section of the armature.

Figure 6 is a diagrammatic scheme of the electric circuits.

Figure 7 is a perspective detail of a portion of the spout partly broken away to disclose the gate.

In Figure 1 a is the gate housing, which may conveniently be either a metal casting or a sheet metal stamping. This member is provided. with a removable head piece 6 and is secured to the main body by means of bolts 0 passing through flanges clformed upon the main body and the head piece. The entire unit is connected with the mill spout e by means of bolts or screws 7", the ad acent upper and lowersections of the spouting abutting if desired internal flanges corresponding to the upper flange of the main body and to the lower'fiange of headmg g of the 1 same. Bythesemeans the housing unit a may be connected with the mill spouting 6 without subjecting the same to any lateral displacement.

The housing a containsa gate-way and gate t of conventional design of which it is the gate stem,

Mounted upon the housing a is a-block or post is, attached to the housing by the bolts Z and carrying a lever 'm pivoted to the block at n and held under compression by the spring 0, this 'springbeing connected to the block it by the bolt 10. The lever m contains a slot or a cam g engaging a pin or pin and rollerr, carried upon the. gate stem It so that the gate may be-oper'ated manually by means ofthis" lever.

Attached to the housing a by the bolts 8 a curving. member 'j having an opening toward its outward extremit throu h which b pose hereinafter descrlbed.

Lastly there is mountedupon the housing a theelectro-magne't .92, being held to the housing by the bolts 3 passing throughits end blocks 2 or alternatively the electromagnet may be attached to a base' block which in turn may be. attached to the housing. s 1

' This electro-magnet wactuates awmovable armature contained within it and this armature acting through an extension ca serves as a detent to engage the notches or teeth w of the gate-stem 72,, holding the gate at any position desired while power is on and disengaging the notches w when the power tails thus permitting the closing of the gate through the action of the spring 0, lever 01, etc., the electro-magnet being in electric connection with the service branches furnishing power to the mill.

The detail of the electro-magnet 03 and its particular operation will now be described.

In Figure 2, b shows the coil or winding, 0 is a sleeve forming a core-piece in which the winding is placed and 2 are the insulating end blocks for the winding and are pressed upon the sleeve 0 Contained within the sleeve 0 and slidable therein is the moving soft iron armature al The armature al is of a length equal to that of the winding 6 and carries at its outer, or lower end as shown in Figure 2, the extension (1- which is composed of aluminum or other non-magnetic material, and this extension has formed upon it at its lower or outer end the detent 6 The extension a is attached to the armature (Z by the threaded pin f and has passing transversely through it a pin 9 by which the armature and detent may conveniently be moved by hand in cases of emergency.

The extension c also carries a screw 71 for the attachment of a controlling spring.

Attached to the lower end block .2 of the electr c-magnet m, by the screws is a conical cap-piece Z of brass or other non-magnetic metal, carrying a short sleeve or collar in -forming a bearing for the extension a and containing within its cavity the control coil spring a surrounding the collar m one end of which spring is attached to the screw 72, of the armature extension (4- while the other end is held in a small recess or boring 0 in the cap Z The function oi" this. spring is to exert an inward or upward pressure upon the extension a Attached: to the upper end block .2 of the electro-magnet m by the screw 21 is a cover plate 9 of non-magnetic material, protecting the cylindrical cavity 0 contained. within, the sleeve 0 above the armature (Z this cover-plate being rotatable about the screw 29 Figure 3 shows a detail of the sleeve This sleeve might be formed of wood-fibre tubing but it is preferable to form it of brass or aluminum. It is essential that it should be non-magnetic. As disclosed in the present specification it is of brass and is constructed with longitudinal slots 3 so as to prevent in as far as possible inductive action of the surrounding coil upon it, the well known action of which would be that the magnetic fluxes generated by the induced currents within the sleeve would oppose and cut down the magnetic lines of force of the inducing currents of the surrounding coil and thereby greatly weaken or practically destroy the magnetic fluxes to be passed through the armature to actuate the latter,

or it instead of alternating current, direct current is being used then it will be a case of the reduction of the total lines of force of the permanent magnetic field and its consequent weakening.

For analogous reasons the armature ex tension a and the cap piece Z are made non-magnetic to prevent distortion of the magnetic field.

In Figure 4 is shown detail of the moving armature al with its extension a and detent 6 7& being the screw for the attachment of the control spring and being the transverse pin, each previously mentioned. The armature proper (Z is grooved or slotted deeply as indicated by j and in the cross section, the purpose of this beino to eliminate, or at least reduce to a minimum, the eddy currents set up in the iron along with their heating eiiect and interference with the useful fluxes passing through the core. The grooving also assists mechanically in the cooling of the armature. Instead of the above structural arrangement of the armature proper a laminated soft-iron armature may be used, but the former design is deemed preferable for the present purpose.

N ow having reference to the several drawings the complete action oi the apparatus is as follows:

When the coil 6 is energized by current flowing through it, magnetic lines of force aass through the iron armature (Z magneti cally polarizing the same and the tension along these lines of force draw or attract the armature etc, downwardly against the action of the control spring 17) until its ends coincide with the planes or lines bounding the extremities of the coil 6 thus causing the detent e on the armature extension a to engage one of the notches or teeth 20 upon the gate-stem h and hold the said stem and its gate at any position to which it may be moved by the lever m.

Upon failure of the power and (lo-energizing of the coil Z the magnetic field acting upon the arn'iature a is 01 course reduced to zero and the now depolarized armature is retracted by the control, spring 122. until the screw 72 abuts the t'ace oi the lower and block o't' the coil in which position the upper end oi the armature (P will register with the straight line wu drawn across the coil perpendicular to its axis, and lying within the cavity 9 this movement resulting in the disengagement of the detent e from the notch w and the consequent closing of the mill spout gate.

As hereinbefore in part described, the terminals ot the coil 5 of the above electric apparatus are connected to the service branches supplying power to the mill into the mill, a a transformer, 1 3 the local circuit leading to the electro-magnets m which are coupled in parallel across the local line 3 3 and 2 and a indicate respectively a main switch and a fuse located upon the ordinary switchboard.

The shunt lines 6 across the branch g may be carried through secondary switches c to admit of the independent cutting out of the local units so. The terminals or binding posts of the local units are indicated by CZ.

The switches 0 are specially designed to give condenser eifects and obviate sparking on opening up the contacts and in addition the contacts have a dust proof cover plate screwed over them, the objects of these precautions being the elimination of the danger of explosion of mill dust. Where the mill spouts are metallic throughout, the entire housing unit of this apparatus may well be insulated.

The local units a" may of course be connected to the service branches to without passing through a transformer, a resistance coil, in this case being cut in at the switchboard on one side of the local line but this results in a wastage of current and is not so satisfactory.

In those exceptional cases where the electric power is direct current, it is obvious that the above arrangement, i. e., the like employment of a special resistance to reduce the current becomes imperative. In the use of direct current the electro-magnets a2 might be designed to give a very high resistance through their coils 6 etc, and the special resistance dispensed with but this would be very disadvantageous practice from an engineering view point.

What we claim is:

1. In mill spout gates, agate valve hav ing a stem extending therefrom, a housing for said valve, means for operating said valve and automatic means for closing said valve coincident with the stoppage of the said mill machinery with which it is adapted to co-operate.

2. In mill spout gates, a gate valve having a stem extending therefrom, a housing for said valve, means for operating said valve, and electro-magnetic means adapted upon de-energization to permit of the closing of said valve co-incident with the stoppage of the mill machinery with which it is adapted to co-operate.

3. In mill spout gates, a gate valve having a stem extending therefrom, a housing for said valve, means for operating said valve and electro-magnetic means operatively connected to said stem and adapted to recede therefrom on de-energization to permit the closing of said valve co-incident with the stoppage of the mill machinery with which it is adapted to co-operate.

4.. In'mill spout gates, a gate valve having a stem extending therefrom, a housing for said valve, manually operated means for raising said valve and electro-magnetic means adapted to be de-energized co-incident with the stoppage of the mill machincry with which it is adapted to co-operate for co-incident closing of said valve.

5. In mill spoutgates, a gate valve having a stem extending therefrom, a housing for said valve, manually operated means for raising said valve, electro-magnetic means operatively connected to said stem adapted upon de-energization consequent upon the stoppage of said mill machinery, to permit of the closing of said valve coincident with the stoppage of said machinery, with which it is adapted to co-operate, and automatic means adapted on the action of said electromagnetic means to quicken the closing of said valve.

6. In mill spout gates, a housing, a gate valve having a ratchet stem extending through said housing, a guide for said stem, a post projecting from said housing, a lever pivoted to saidpost and adjustably engaging said stem for raising said valve, electromagnetic means normally in operative engagement with said ratchet stem and a main electric circuit suitably energized and including various translating devices, and said electro-magnetic means.

7. In mill spout gates, a housing, a gate valve having a ratchet stem extending through said housing, a guide for said stem, a hand lever operatively connected to said stem, spring means exerting inward pressure on said lever to close said gate, an electric circuit, an electro-magnet connecting with said electric circuit and comprising a core piece adapted to carry windings, end blocks carried by said core piece, a movable armature slidable within said core piece and having a nonmagnetic extension therefrom, a detent carried by said extension and adapted normally to engage said ratchet stem, a cap secured over one end of said electro-magnet and slotted to slidably accommodatc said extension and a spring located within said cap and exerting inward pressure on said extension to disengage said detent from said ratchet stem upon the deenergization of said electro-magnet.

Signed at the city of Toronto, Province of Ontario, this 12th day of August, 1919.

lVitnesses:

WV. G. HAMMOND, C. A. RICHARDSON. 

